The study presents analysis of the properties and parameters of waste from high-temperature processing of mineral raw materials – blast-furnace and steelmaking slags, dump slags from copper smelting and ferrochrome production, and incinerator slag. We perform a detailed analysis of the material composition of the studied materials, identify key resource and environmentally significant indicators of the chemical composition and physical properties of the waste, and adopt these as indicators of the resource and environmental potential of the slags. The paper considers approaches to grouping raw materials of industrial origin into categories with similar resource value and environmental hazard. As an alternative for classifying waste from high-temperature processes, we propose a cluster-based approach that enables building a categorization system for industrial raw materials according to their properties and limiting the number of sampling features while maintaining sufficient coverage of the classified materials. After standardizing and checking the multicollinearity of the selected indicators of the slags’ resource and environmental potential in the analysed dataset, the study finds that most indicators show low, absent, or random correlation. Using the Statistica software, we rank the studied materials via fuzzy clustering. Based on the resulting distribution, we define three cluster groups for treatment: resource-inert; resource-valuable with moderate environmental impact; and environmentally hazardous, requiring deep processing. The results show that granulated blast-furnace slags, lump blast-furnace slag, and ferrochrome production slag are suitable for manufacturing construction materials without preliminary dressing, provided the products meet environmental safety requirements. Steelmaking slags represent a resource-valuable material with moderate environmental impact and are suitable for producing metal concentrate. Copper-bearing slags and incinerator slags are environmentally hazardous and require deep processing with metal recovery, while tailings need stabilization and neutralization. The obtained results form the basis for further development of a methodology for comprehensive resource and environmental assessment of industrial mineral facilities, which is necessary for transitioning to closed-loop production cycles.